A Breakthrough of Glucose Biosensing Technology based on Complete Oxidation Process

The importance of non-invasive, real-time biomarker monitoring is paramount in disease prevention, diagnosis, and health management. Consider glucose sensing as an illustrative example. This process hinges on the detection of signals (or electrons) emanating from the glucose oxidation reaction (GOR). Contemporary sensing materials are limited to a 2-electron oxidation process, which curtails sensitivity enhancements. Given that glucose is a multicarbon compound capable of undergoing complete oxidation to release up to 24 electrons, fully harnessing this potential is a key yet challenging objective.

A new study published in Angewandte Chemie International Edition by Xiaoyue Shi, Yiqi Ling, Youcong Li, Guanhua Li, Juan Li, Lingwei Wang, Fanhong Min, René Hübner, Shuai Yuan, Jinhua Zhan, and Professor Bin Cai from the Shandong University and Helmholtz-Zentrum Dresden-Rossendorf, researchers conducted a detailed investigation to address the challenges associated with glucose electrocatalysis. Their work aims to create a highly sensitive glucose electrochemical sensor. The novel sensor incorporates a copper hydroxide-organic framework material (Cu-MHOF) as the sensing layer, effectively achieving glucose’s complete oxidation and thus substantially amplifying signal detection. This advancement has led to the development of a portable, wireless glucose sensor for dynamic monitoring of glucose in human body fluids.

The study highlights the inherent advantage of Cu(OH)2 in catalyzing glucose oxidation, which can spontaneously catalyze glucose oxidation and release 2 electrons via instantaneous thermal catalysis. The team designed a Cu-MHOF catalyst, linking Cu(OH)2 layers with aromatic carboxylic acid ligands. These aromatic ligands create strong π-π interactions, bolstering structural stability and exposing numerous unsaturated Cu sites. These sites, in conjunction with the aromatic ligands, are pivotal in adsorbing reactants and intermediates, thus facilitating complete oxidation. The Cu-MHOF exhibits a 40-fold increase in glucose oxidation-sensing signal compared to Cu(OH)2 nanomaterials. The researchers employed various methods, including isotope labeling, to elucidate the deep oxidation mechanism of glucose.

Collaborating with Shenzhen Refresher Biosensing Technology Co., Ltd., the research team has engineered a compact, portable Cu-MHOF glucose electrochemical sensor, capable of sensitively detecting low-concentration glucose. The sensor demonstrates excellent performance in dynamically monitoring human saliva glucose levels.

The non-invasive glucose monitoring system, incorporating this electrochemical sensor, comprises three main components: a client-side application (APP), cloud, and hardware devices. This user-friendly system allows operation via smartphone or tablet, with real-time recording and querying of test results, and cloud synchronization. Healthcare professionals can offer medical guidance based on cloud-based results, enabling users to adjust diet or medication accordingly.